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How do tectonic uplift and erosion work together to shape plateaus?

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plateau The Columbia Plateau is uniformly covered with basaltic lava flows and spans an area of about 100,000 square miles in Idaho, Washington, and Oregon.

Tectonic uplift and erosion work in tandem to create and modify plateaus, with tectonic processes acting as the "builder" and erosion serving as the "sculptor".1

Tectonic Uplift
Tectonic processes establish the high elevation of a plateau through three primary mechanisms:
* Thermal expansion: Heating of the lithosphere causes the surface to rise.21
* Crustal shortening: Folding or thrusting of crustal layers thickens the crust, pushing the surface upward.21
* Volcanism: Extensive lava flows, such as flood basalts, bury existing terrain to create new, elevated surfaces.21

The Role of Erosion
While tectonic forces build the structure, erosion shapes its final appearance. Erosion acts to reduce elevation differences, often carving deep canyons or valleys into the plateau surface. In some regions, such as the eastern Plateau of Tibet, intense river erosion can be so significant that the original flat surface is replaced by a landscape of steep ridges and deep canyons, leaving the plateau's uniform elevation only barely discernible. Conversely, in dry climates where erosion is slow, plateaus can persist for hundreds of millions of years.123